Temporal and spatial variation of free calcium with contraction in isolated cardiac myocytes

摘要

Abstract: Recent advances in the development of calcium-sensitive fluorescent dyes and spectrofluorometry have greatly increased their use in assessing transient changes in free cytosolic calcium during contraction of single isolated cardiac myocytes. The same fluorescent images used for this purpose can be captured using a video frame-grabber for subsequent analysis of the distribution of free calcium within each myocyte, and also provide excellent contrast for edge-detection systems used to track changes in myocyte length during contraction. We have applied these techniques to the study of differences in free calcium concentration and contraction in normal ventricular myocytes and in myocytes obtained from hypertrophied failing hearts. In the process, we have sought to optimize our equipment and procedures to meet specific needs. Progress with cell imaging, signal averaging, and data acquisition and processing is described in the context of our experimental objectives.!5